Filmpack for multicolor photography



March 19, 1935. A. VON BIEHLER 1,994,627

FILMPACK FOR MULTICOLOR PHOTOGRAPHY Filed Dec. 5, 1931 sent... M...19,1935 1,994,627

UNITED STATES PATENT orrics FILMIACK FOB MULTIUOLOB PHOTOGRAPHY Arpadvon Biebler, Dessau, Germany, assignor to Agfa Ansco Corporation,Bingliamton, N. Y a

corporation of New York 6 Application December 5, 1931, Serial No.557%),269

In Germany, December 10, N30 w 17 Claims; (-91. 95--2) My presentinvention relates to a filmpack for the pictures are taken in such amanner that multi-color photography. the object is taken at times insuccession with the I One of its objects is to provide an improved sametime oi exposure, nbeing in general 3. Befilmpack for multl-colorphotography. Further tween the diiferenirexposures it is only necessaryobjects will be seen from the detailed specification to draw the tab,there being no necessity for the following hereafter. provision ofanother selection filter and regula- It is known to prepare multi-colorpictures by tion the Shutter 1 f the appar tu A taking in successionseveral partial color sensamost this process requires a compensationfilter tion records of the object to be photographed which, however,remains the same for the expo- 10 on layers having a difierent spectralsensitiveness. sures of all partial sensation records. 10

. This known process, however, is complicated, since This compensationfilter is inserted in the way for taking each partial picture theobjective has of the light rays before reaching the film if the to beprovided with another filter and the time of illumination for taking thepicture is dlfierent exposure of the apparatus has to be changed owfromthat used for adopting the difierently sensiing to ,the differentthresholds of perception of tized films to each other. It is obviousthat the 15 theemulsion layers. partial color sensation records made inquick suc- My improved filmpack allows of simplifying ccssion by drawingthe tabs and by actuating the this troublesome handling. The filmpackconshutter adjusted to the some" time of exposure tains as usual filmsbeing disposed one behind the wanted must be taken with the sameillumination.

other and having emulsion layers sensitized for The adaptation oi thediilerently sensitized films 20' different spectral regions, but beforethe films to the some minimum exposure value must be there are disposedcorrection filters. These filefiected with a distinct illumination, forinstance, ters serve on the one hand for absorbing the with daylight ofmiddle value. The sensitiveness light rays which shall not act upon thefilm,to be of the films does no longer harmonize, if the taken, on theother hand for adapting the sensii umination is changed, for instance,when 11- 25 tiveness of the films intended to receive the difluminatingwith the red light of the setting sun or ierent partial'color picturesto each other, in with artificial illumination (nitra-li The order toallow all partial color pictures to be made harmony of thesensitiveness'can, however, easily with the same time of exposure. Inthe case of be regained when inserting before the objective to producinga certain color'sensation, for instance, a mp nsat n fi t r w h s the sm for a red or 'a green sensation, a yellow colored filter ing allpartial color sensation records. In the is used which subdues the lightrays of the blue present case, illuminating with nitra-light a part ofthe spectrum (to which the emulsion is blue-green filter is necessary.if the adaptation normally sensitive). This yellow correction filter oithe differently sensitized films was effected can be adjusted byaddition of a neutral grey dye with nitra-light, for taking pictureswith daylight if the sensitiveness of the layerssensitized for red anorange filter is to be inserted before the oband greendoes not harmonizefor a distinct imjective. pression. The sensitiveness of the third filmAccording to one mode of execution of my inwhich is sensitive for bluecan be adjusted to the vention the correction filter is cast on theemul- 40. sensitiveness oi the other two films by inserting sion layer.This may he performed ior instance, 40 a yellow or a grey filter ofsuitable density or by by covering the emulsion layer with a gelatininserting before the objective a yellow filter of layer and providing onthe latter a coating of suitable density. In the latter case the filteracts fiuorescein ammonia from a solution or this dye as a commoncompensation filter for all films but in alcohol. Still another way isto cover the has a material influence only on the film sensitiveemulsion layer with a gelatinjayer, the gelatin 45 for blue since theother two films are already solution irom which the layer is made being,for provided with a yellow filter of higher density instance, dyed withfienzo Light Yellow R L (of. which practically absorbs all blue lightrays. In Piers-David Kiinstliche organische Farbstofie this manner byinserting correction filters, the 1926, S. 168). The fluorescein ammonialayer is 0 spectral sensitiveness and the minimum exposure removed inthe developing and fixing bath, the

value required to obtain the impression on the gelatinlayer containingBenzo Light Yellow R L layers are adapted to one another so that all'theis decolorlzed by an acidified solution of sodium emulsion layers haveduring the photographic hydrosulfite. operation the same minimumexposure value. Another mode of execution of my invention con- 5 Withthe filmpack according to my invention in providing. the correctionfilter by inserting them in form or a separate foil before the emulsionlayer of the film and to connect them in the same manner as the filmwith thedraw tab. After having taken the partial picture the filter canbe drawn from the exposure window into the chamber of the filmpacktogether with the film lying behind it.

Finally, it is possible to form the gelatin layer usually applied to theback of a film in a filter, by giving it suitable coloration. As dyesimparting to this gelatin layer the desired coloration, for instance, Imention tartrazine, filter yellow and quinolin yellow. In this case theexposure is effected through the layer support.

For softening the yellow correction filters neutral grey G (of. Schultz,Farbstofitabellen 1931 (A) 551) is used, or if the filter is cast on theemulsion layer an addition of, for instance, lampblack, graphite orfinely divided silver may be made to the filter layer.

The following example serves to illustrate m invention.

A highly sensitive negative emulsion for cinematographic film is dividedinto three parts. One part is not sensitized and cast on a celluloidsupport which is provided on its rear side with a gelatin layer of 15 athickness. This back layer contains on grams of gelatin 1 gram oftartrazin. The second part of the emulsion is sensitized for green withaid of pinafiavol or erythrosin and cast on a celluloid support carryingon its rear side a gelatin layer of 15 a thickness. This back layercontains on 100 grams of gelatin about 8 grams of tartrazin. The thirdpart of the emulsion is sensitized for red with the aid of pinacyanolblue and is cast on 'a celluloid support having on its rear side agelatin layer of 15 a thickness, This back layer contains on 100 gramsof gelatin, about 8 grams of tartrazin. For ascertaining thesensitiveness of the different films a grey scale is taken by exposingeach film the same period of time through the yellow rear side whileilluminating with the same source of light and using differentcorrection filters. In this manner the correction filters are determinedwhich yields identic negatives in the three partial layers for the sametime of exposure.

1 ii, for instance, the negatives on the layer sensitized for green andthat sensitized for red are identic, and the negative on the layer whichis not sensitized is still superexposed the correction filter must onlybe chosen in a somewhat darker shade for obtaining conformity. If theblackenings of the negative in the layer sensitized for green are tolight, for instance, a correction filter having a light gree color isused.

Instead of start g from one single emulsion there can be employedemulsions each having different sensitiveness. In this case, however,the curve 'of gradation of the different emulsions must be identic. Thiscan be efiected by incorporating. for instance, a yellow dye in theemulsion layer sensitive to the blue light rays, a red dye to theemulsion layer sensitive to the green light rays and a green dye to theemulsion layer sensitive to the red light rays.

My invention is illustrated in the accompanying drawing, the samereference characters denoting the same parts.

Fig. 1 represents a perspective view of my new filmpack, the coveringpaper as well as the first three tabs having been drawn to-a certainextent. 1 designates the casing of the filmpack. The tabs are markedwith 2. The covering paper 3 is nearly wholly removed so that thepartially drawn first three films 4, 5 and 6 can be seen. These threefilms are sensitized tor the red, green and blue spectral region andintended for taking the three partial color sensation records of a threecolor picture. different filters thru which the picture is taken.

Two modifications of such an arrangement are shown in Figs. 2 and 3. Inthese figures the three films provided with the tab 2 and belonging tothe same group are marked 4, 5 and 6.

In Fig. 2 the film support 7 bears an emulsion layer 8 and is connectedto the tab 2. The correction filter 9 forms in this modification aseparate foil which for the sake of cleamess is shown somewhat removedfrom the film, but which lies adjacent to the emulsion layer in thefilmpack. The filter foil is likewise connected to the tab 2. In thismanner the film and filter are drawn together.

In Fig. 3 the emulsion layer 8 is provided on the film support 7 andlies adjacent to the tab 2. The correction filter is formed by a dyedthin gelatin layer cast on the back side of the film support. The filmand the filter form in this case one part being connected to the tab.The exposure of the film is made through the support.

I do not wish to limit my invention to the foregoing examples nor to thespecific details given therein. Numerous other filter dyes than thosementioned and which are well known to every chemist skilled in the artmay be employed, and a few simple comparative experiments should .bemade in order to determine the most suitable dye for the correc ionfilter and the most suitable amount of the dye to. be employed in eachparticular case. The same holds true with regard to the compensationfilter. Furthermore I do not wish to limit my invention to the specialuse of filmpacks, other packings such as roll films or evencinematographic films having arranged in succession partial filmssensitized for difierent spectral regions, which allow of takingmulti-color pictures are likewise intended to be included within thescope of my present invention.

What I claim is:

l. A package for multi-color photography comprising arranged insuccession as many photographic films as correspond with the number orber of partial colorsto be taken, and an opaque means between twosuccessive films, each film being sensitized for a difierent spectralregion and each film'being provided with a yellow filter containing inaddition a grey dyestuflf, said filters having such a strength that thefilms can be taken successively with the same time of exposure whenilluminated with a certain source of light.

3. A package for multi-color photography com The three films areprovided with prising arranged in succession at least one series orthree films sensitized for difierent spectral regions and provided witha yellow filter of such a strength that the films can be takensuccessively with the same time or exposure when illuminated with acertain source or light.

4. 'A package for multi-color photography comprising arranged insuccession at least one series of the three films sensitized fordifierent spectral regions and an opaque means between two successivefilms, each of said films being provided with a yellow filter containinga grey dyestuff, said filters havingsuch a strength that the films canbe taken successively with the same time of exposure when illuminatedwith a certain source of light.

5. A package for multi-color photography com prising arranged insuccession as many photo graphic films as correspond with the number ofpartial color pictures to be taken, and an opaque means between two'successive films, each film being sensitized for a difierentspectralregion and each film being provided with a yellow filter containing inaddition a dye for subduing the action of the light to which theparticular film is sensitive, said filter having such a strength thatthe films can be taken successively with the same time of exposure whenilluminated with a certain source of light.

6. A multi-color film pack comprising arranged in succession at leastone series of three films sensitized for different spectral regions andan opaque means between two successive films, each of said films beingprovided with a yellow filter containing in addition a dye for subduinuthe 1 action or the light to which the particular film iii is sensitive,said filter having such a strength that the films can be takensuccessively with the same time or exposure when illuminated with acertain source of light.

'7. In multi-color photography in combination a package comprisingarranged in succession as many photographic films as correspond with thenumber of partial color pictures to be taken, and an opaque meansbetween two successive films, each film being sensitized for a difierentspectral region and each film being provided with a yellow filter ofsuch a. strength that the films can be taken successively with the sametime of exposure when illuminated with a certain source of light, and acompensation filter adapting the films of said package toanother sourceof light, so that they can be taken with the same time of exposure. r 8.In multi-color photography in combination a package comprising arrangedin succession as many photographic films as correspond with the numberof partial colors to be taken, and an opaque means between twosuccessive films, each film being sensitized for a different spectralre-=- gion and each film being provided with a yellow filter containinginaddition a grey dyestuil, said filters having such a strength that thefilms can be taken successively with the same time of exposure whenilluminated with a certain source of light, and a compensation filteradapting the films of said package to another source of light, so thatthey can be taken with the same time of exposure.

9. In multi-color photography in combination a package comprisingarranged in;succession at least one series of three films sensitized fordifferent spectral regions and provided with a yellow filter of such astrength that the films can be taken successively with the same time ofexposure when illuminated with a certain source of light, and acompensation filter adapting the films of said package to another sourceof light, so that they can be taken with the same time of exposure.

10. In multi-color photography in combination a package comprisingarranged in succession at least one series or three films sensitized fordifferent spectral regions and an opaque means be-= tween two successivefilms each of said films being provided with a yellow filter containinga grey dyestufif, said filters having such a strength that the films canbe taken successively with the same time of exposure when illuminatedwith a certain source of light, and a compensation filter adapting thefilms of said package to another source of light, so that they can be"taken with the same time or exposure.

11. In multi-color photography in combination a package comprisingarranged in succession as many photographic films as correspond with thenumber of partial color pictures to be taken, and an opaque meansbetween two successive films, each film being sensitized for a difierentspectral region and each film. being provided with a yellow filtercontaining in addition a dye for subduing the action of the light towhich the particular film is sensitive, said filter having such astrength that the films can be taken successively with the same time ofexposure when illuminated with a certain source of light, and acompensation filter adapting the films or said package to another sourceof light, so that they can be taken with the same time of exposure.

12. In multi-color photography in combination a package comprisingarranged in succession at least one series of three films sensitized fordiflierent spectral regions and an opaque means between two successivefilms, each of said films being provided with a yellow filter containingin addition a dye for subduing the action of the light to which theparticular film is sensitive, said filter having such a strength thatthe films can be taken successively with the same time of exposure whenilluminated with a certain source of light, and a compensation filteradapting the films or said package to another source of light, so thatthey can be taken with the same time of exposure.

13. A package for multi-color photography comprising arranged insuccession at least one series of three films sensitized for differentspectral regions and an opaque means between two successive films, eachof said films being provided with a filter layer of gelatin coated withfluorescein ammonia of such a strength that the films can be taken andan opaque means between two successive films, with the same time ofexposure when illuminated with a certain source of light.

14. A package for multi-color photography comprising arranged insuccession at least one series of three films sensitized for diflerentspectral regions and an opaque means between two successive films, eachof said films being provided with a filter dyed Benzolight Yellow RLcontaining Neutral Grey G, said filters having such a strength that thefilms can be taken, and an opaque means between two successive films,with the same time of exposure when illuminated with a certain source oflight.

15. A package for multi-color photography comprising arranged insuccession three films having coated orr a support an emulsion layer ofthe same emulsion, an opaque means between two successive films, thefirst film being not specially sensitized and carrying on its rear sidea gelatin layer of a thickness containing 1 gram of tartrazine on megrams of gelatin, the second film being sensitized for green withpinafiavol and carrying on its rear side a gelatin layer of 15 ;&thickness containing 8 grams of tartrazine on 100 grams of gelatin, thethird film being sensitized for red with plnacyanol and carrying on itsrear side a gelatin layer of 15 a thickness containing 8 grams oftartrazine on 100 grams of gelatin.

16. In multi-color photography in combination a package comprisingarranged in succession at least one series of three films sensitmed fordifferent spectral regions and provided with a filter layer of gelatincoated with fluorescein ammonia of such a strength that the films can betaken successively with the same time of exposure when illuminated witha certain source of light, and a compensation filter adapting the films01 said; package to another source of light, so that they can be takenwith the same time of! mama? 17. In multi-color photography incombination a package comprising arranged in succession at least oneseries of three films sensitized for different spectral regions and anopaque means between two successive films each of said films beingprovided with a filter dyed Benzolight Yellow RL containing Neutral GreyG, said filters having such a strength that the films can be takensuccessively with the same time of exposure when illuminated, and acertain source 01 light with a compensation filter adapting the films ofsaid package to another source of light, so that they can be taken withthe same time of exposure.

ARPAD von BIEHLER.

